A high resolution time-of-flight 252Cf-PDMS system now under construction will be completed and applied to biomedically related problems. It will feature a new design for the 252Cf source within proved efficiency, computer-controlled detector alignment and precise mechanical alignment. Efforts to extend the mass range beyond M equals 13,000 will be made using block Co-polymers in the mass range 5000-50,000 as model compounds. Work will continue on improving yields of molecular ion production of large peptides (insulin, beta-lacta globulin) and on applications of 252Cf-PDMS to the analysis of synthetic gene fragments. Detailed studies will be carried out on the 252Cf-PDMS of selected classes of antibiotics that are studied with great difficulty by F.D. Finally, 252Cf-PDMS analyses of slow reacting substances (SRS) will be carried out in collaborative projects to assist in structure determination.